A Seminar on STEAM FLOW METER PRESENTED BY:- GHANSHYAM PRAKASH INSTRUMENTATION E.CODE:

1.Reqiured in 3-elemrnt drum level control of boilers. 2. To calculate the efficiency (Boiler ssc & Turbine ssc.) 3.To Analyze the losses (venting, Tube Leakage) IMPORTANCE OF STEAM FLOW METER

1.HOW TO TAKE STEAM FLOW TX IN LINE 1.Check all valves closed. 2.Open the equalizing valve. i.e., zero differential pressure. 3.Open the High Pressure block valve slowly. 4.Close the equalizing valve. 5.Open the low-pressure block valve. 6.The transmitter is now in service 2.Removing STEAM FLOW Transmitter from Service. 1.Close the low-pressure block valve. 2. Open the equalizing valve. 3. Close the high-pressure block valve.

FLOW ORIFICE

INSTALLATION OF ORIFICE PLATE 1.flange tap:- hole are bored in flange located one inch upsteam and one inch down stream from respective faces of orifice plate.. 2.VENA CONTRA TAP:- One pipe inner diameter towards upstream and one half inner pipe diameter downstream. 3.Pipe Tap:- two and half inner diameter in upstream and 8 inner diameter toward down stream.

ORIFICE PLATE ADVANTAGE DISADVANTAGE:-

Flow Nozzle Installation 1. lower presser loss than orifice but more than venturi tube. 2. used at high velocity flow measurement like feed water 3. More resistant to erosion than orifice plate

CUT -OFF RELAY 1.SQUARE ROOT EXTRACOR HAVE HIGH GAIN VALUE CLOSE TO ZERO INPUT. 2. DUE TO NOISE,TEMP OR OTHER DISTURBANCE,FLOW SHOW 1% EVEN VALVE IS CLOSED. SO A CUTOFF RELAY IS REQIRED WITH A CERTAIN SETTING. SO THE SIGNAL BELOW THIS SETTING WILL BE IGNORED BY THE EXTRACTOR.

DENSITY COMPENSATION 1. K depend on pipe size and characteristics of fluid 2. Flow= sensor value x square root C1xC2 3.Where, C1=Sq root( Live Pr / design pressure+1.033) C2= sq root (design temp+ 273/ Live temp+ 273)

Mathematical calculation Energy associated with fluid: 1.Potential Energy: density x gravity x height. 2.K.E= 1/2xdensityxsq. Velocity 3.Pressure energy= density x velocity 4.Heat energy = Resistance to flow, viscosity 5.As, diff press= ½ density x (sq v2- sq V1) Continuity equation:- A1V1=A2V2 V2= A1/A2 Flow equation= CA2/sq(1-sq(A2/A1)) A2=area of down stream pipe A1= area of Up Stream pipe

Measurement errors. 1. ERROSION:- Orifice is more affected by the erosion caused by suspended solids as tear and wear occur decreases and flow goes down. 2.VAPOUR FORMATION IN HP AND LP THROAT:- LP SIDE THROATING SHOW HIGHER FLOW RATE THAN ACTUAL.HP SIDE CAVITATION CAUSE LESSER FLOW RATE. 3.PLUGGED OR LEAKAGE IN IMPULSE LINE: LP side leakage- High reading HP side Leakage- Low reading Clogging of Throat of sensor. Equalizer Manifold Leakage